Fuse plug



Dec. 8, 1931. j SHELLER 1,835,905

FUSE PLUG Filed Dec. 11, 1929 IN VEN TOR.

g7 'II I BY 9229; @1 WTTORNEYS.

Patented Dec. 8, 1931 UNITED STATES PATENT OFFICE JOHN C. SHELLER, 01 CHICAGO, ILLINOIS, ASSIGNOR OF ONE-HALF TO FBAN K E. WHITE,

OF CHICAGO, ILLINOIS, .fiND ONE-HALF TO WALTER B. HINTZE, OF CHICAGO, ILLINOIS FUSE PLUG Application filed December 11, 1929. Serial No. 413,282.

This invention relates to fuse plugs. The object of my invention is the construction of a simple and efficient plug which can I be used to plug in for electric irons, sweepers, connections or extensions, etc.

Another object of my invention is the improvement of the construction of the positive and negative contact devices of a plug, whereby a very eificient and practical device is produced at a relatively low cost of construction.

With the foregoing and other objects in View, my invention comprises certain novel constructions, combinations and arrangements of parts as will be hereinafter fully described, illustrated in the accompanying drawings, and more particularly pointed out in the appended claims.

In the drawings:

Figure 1 is a view in side elevation of the socket plug and indicator plug in an assembled position, with the locking or connecting sleeve shown insection.

Figure 2 is a longitudinal central sectional view of my socket plug, while Figure 3 is a view in elevation looking at the inner end of the same.

Figure is a perspective View of the negative Contact device of my plug.

Figure 5 is a perspective view of the positive contact device of my plug.

Figure 6 is a view in elevation, looking at the inner end of the locking or connecting sleeve.

Figure 7 is a view in elevation looking at the inner end of the indicator plug, while Figure 8 is a lon itudinal central sectional view of the same.

Figure 9 is a plan view of the fuse.

Referring to the drawings by numerals, my socket plug comprises a body 1 formed of any suitable non-conducting material, such as porcelain, and carried by the body are the positive contact device 2 (Fig. 5) and the negative contact device 3 (Fig. 4).

The positive contact device 2 is substantially L-shape including the body 4 and the foot 5. Extending laterally and inwardly from body 4- is a dovetail tenon 6; this clovetail tenon is arranged near the middle of the body 4. The body 4 and the tenon 6 are molded into the body 1 during the manufacture of the same, with the outer face of the foot 5 lying in the same plane as the inner face of the body 1 (Fig. The body 1 is provided with two blade or prong sockets 7 with the inner bevelled end of body 4 extending into one of these sockets.

The negative contact device 3 comprises an enlarged body 8 from which extends :1 prong 9. This prong 9 is similarly bevelled at its outer end to the bevelled structure of the outer end of body 4. Integral with and extending outwardly from body 8 is a dovetail tenon 10; the prong 9 extends outwardly from body 8 near its center (Fig. 4). The prong 9 extends into one of the sockets 7 similar to the body 4. The outer face of body 8 is provided with grooves 11 that constitute part of the screw thread grooves 12 (Fig. 1) of the non-conducting body 1.

The prong sockets 7 are sufiiciently large to allow the usual prongs of a connecting device of asweeper or curling iron or the like to be inserted thereinto, in contact with the positive and negative contact devices of the plug. It is to be understood that the foot of the positive contact device permits the current from the source of supply to pass into the plug whereas the return current flows through the negative device and is grounded, on the receptacle in which the plug is screwed. The large or bulged body 8 of the negative contact device 3 does not extend to the edge of the inner face of the body 1, but terminates short thereof, as is clearly seen in Figure 2., The body 1 is provided with an annular flange 12, which is notched at 13, 13 for the purpose hereinafter specified. The bevelling of the portions of the positive and negative contact devices that are positioned in the sockets 7 is done to allow free insertion into said sockets of the prongs of the indicator plug, hereinafter described or of any extension unit for a sweeper or curling iron or the like.

My indicator plug (Figs. 7, 8 and 9) comprises a body 14 which has a compartment 15 in which moves the head 16 on the inner end of the indicator 17. The body 14 is provided .with an annular flange 18 that is notched at in sockets which are'iilled with preferably socket-plug,

wax 2st;- by removing the war; 2% access to the head'is easily obtained. A. fuse 25 1S placed upon the pron s-21 and when the fuse.

is blown, the indicator 1'? will be projected a considerable distance indicating that the fuse has been destroyed. In the inner face or end of body let are also wire receiving grooves 26. i V When the indicator plug is placed upon the as shown in Figure 1 and'the locking or connecting sleeve 27 is placed in position, the inwardly extending lugs 28 will have passed through: the registering notches 13 and 19 and as the operator will have sli htly turned this sleeve tocause lugs 28 to en gage the flange 12,'the parts will be securely fastened together against accidental displacement. By turning the sleeve sothat the lugs 28 will register with thenotches 13 and 19, the sleeve can be quickly removed, and thenthe indicator plug and the socket plug may be separated.

\Vhile I have described the preferred einbodiment of my invention and illustrated the same in the accompanying drawings, certain minor cliangesor alterations may appear to one skilled in the art to, which. this invention relates during the extensive manufacture of the same, and I- therei'ore, reserve the right to make such changesor alterations asshall fair- 1y fall within the scope of the appended clain1s.

What I: claim is:" r 1 H V 1. In a. device of the classdescribed, the combination of a. body, a. negative contact devicetormed as an integral part of said body,,said contact device comprising a bulged body, .aprong extending outwardly from said body near itsfcentena laterally extendingdove-tail tenon formed: on said bul ed body at one side and grooves formed on the opposite side of said body, said first men-' tione'd. body provided with screw thread grooves and said grooves on the contact body registering therewith, and a. positive contact device formed in said body.

r 2. Ina device of the class described, the

combinationoi a-body, a piston comp artment in saidbo-dy, said body provided onits inner face with transverse grooves, prongs seated in said grooves, screws extending through portions of said body and into said: prongs, said body, provided with screw head sockets,

said screws having their heads seated in said sockets, filling means normally-closing said screw hoad sockets, and an. indicator provided with a head movably mounted in said piston compartment.

3. In a. device of the class described, the combination of a body provided with a piston compartment, said body provided with a transverse groove and with wire-receiving sockets, prongs seated in said transverse groove, screws extending through part of said body and threaded lnto said prongs, a removable fuse on said prongs contiguous to said piston compartment, and a movable indicator in said piston compartment normally against said fuse.

Ion-a device of the class described, the combination of a socket plug and an indicator plug having their inner ends in engagement, said plugs provided on their inner ends with registering-flanges, one or said flanges pro:

vided with lug-receiving notches, a locking sleeve mounted on said flanges, and said looking sl-eve provided with lugs adapted to pass through said: notches and engage the outer face of one of said flanges for lockingthe plugs together.

5,111 adevice of the class described, the combination of a body provided with an outwardly-extending annular fiange,,said flange provided with transverse notches, an indicator plug provided with an outwardly-extending annular"flange registering with said flange of the body, a locking sleeve mounted on said flange of the indicatorplug and engaging the side of said flange of the body, and said locking sleeve provided with in- \vardly-extending lugs passed through said transverse notches and engaging the outer face of'said firstkmentioned annular flange.

In testimony whereof I hereunto affix my signature. 7

JOHN; C. SHELLER. 

